Adapter for use in non-lethal weapons and ammunition

ABSTRACT

A telescopically expandable cartridge comprising an anterior portion  1  and posterior portion  2,  the posterior portion  2  carries a first primer  3  which when initiated releases gases which propel a ball  4  along a channel  5  to impact upon a second primer  6  in the anterior portion  1.  First primer  3  is configured for centre firing. The cartridge is located in the barrel of a weapon which has an off set firing pin  7.  An adapter  8  is received in a recess in the posterior portion  2  to the rear of the first primer  3  and directly in front of the firing pin  7.  The adapter  8  comprises a cylindrical body having an annular recess  9  provided around its outer circumference. An O-ring  10  is received in the annular recess  9.  On an anterior surface of the adapter  8  proximal to the first primer  3  is provided a pointed protrusion  11  positioned centrally of the anterior surface.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority from United Kingdom Patent Application No. 1205712.1 filed on Mar. 30, 2012, of which the contents are incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to an improved method of adapting a cartridge with a centre fire primer so that it can be fired by a weapon with an offset firing pin.

The Applicant's earlier published patent application WO 01/59398 describes various modifications of a gun to replace its centrally located firing pin with an offset firing pin. The adapted gun is proposed for use in combination with a non-lethal cartridge which is provided with rim fire primer. Thus a lethal weapon is rendered non-lethal as it is no longer able to fire lethal, centre fire primer ammunition and is suited for use in training applications firing the applicant's rim fire primer cartridges.

Prior to the Applicant's invention described in WO 01/59398, non-lethal ammunition was available with a centre fire primer. The Applicant's previous invention recognised that if both the non-lethal and lethal cartridges were fired by a centre fire pin, there was considerable risk of an accident if the lethal and non-lethal ammunition became confused. However, a number of problems are associated with the manufacture and use of rim fire primer cartridges, including the cost of manufacturing the rim fire primers and cartridges including such primers, their availability, and toxicity of the currently available rim fire primers. Accordingly, non-lethal cartridges are still produced which have centre fire primers.

SUMMARY OF THE INVENTION

The present invention seeks to provide a device which can be used swiftly to adapt a centre fire non-lethal cartridge to be suited for firing by a weapon with an offset firing pin. The adaptation is conveniently reversible if the cartridge has application in both centre firing and rim firing weapons.

In accordance with the present invention, there is provided an adapter for translating an impact in an off centre location of the adapter to an impact in a centre location whereby to facilitate the firing of a centre fire primer cartridge by a weapon with an offset firing pin. The present invention maintains the safety of a weapon having an offset firing pin which is designed to prevent the weapon from firing lethal ammunition, while also allowing non-lethal cartridges having lower cost centre fire primers to be used in such a weapon.

In a simple embodiment, the device comprises a rigid cylinder having a closed end on which is provided a centrally positioned protruding point. For example, the closed end of the cylinder may have a centrally positioned substantially conical protrusion. The cylinder is shaped to fit snugly but not immovably in a bore in an end of the cartridge. In use, the protruding point is located against the centre fire primer of the cartridge. When the gun is fired, the firing pin impacts the periphery of the cylinder creating a thrust against the adapter, the cylinder carries this thrust to the protruding point which impacts upon and initiates the centre fire primer of the cartridge.

The cylinder may be completely solid or have one open end and a hollow centre. Desirably, the adapter incorporates an annular seal about its outer circumference to prevent leakage of gaseous products from the rear of a fired cartridge during use. The seal may conveniently be provided in the form of a rubber O-ring located in an annular recess provided around the outer circumference of the cylinder. In an alternative, the seal may be formed integrally with the cylinder. For example, the cylinder may be crimped about its outer circumference to facilitate sealing with the cartridge during use.

The adapter may comprise a single piece or modular components suitably assembled. Most conveniently the adapter comprises a unitary body which may be manufactured by any suitable method. For example, the unitary body may be moulded, cast, extruded and/or machined to the desired shape. Likewise, where the adapter comprises modular components suitably assembled, the individual components may be moulded, cast, extruded and/or machined to the desired shape.

A variety of materials may be used for the purpose but material use is restricted to one which is solid, hard and inert in the presence of primer gases. For example, the adapter may be comprised substantially of metal, a metal alloy, or a rigid plastic. Preferred metals and metal alloys include aluminium, titanium, brass, steel, such as stainless steel, and titanium alloys. Where the adapter comprises modular components suitably assembled, the individual components may be made from the same material or may be made from different materials.

In one embodiment, the adapter comprises a metal body, for example a steel, titanium or aluminium alloy. Hard, inert plastics materials may provide a suitable alternative.

The arrangement has been found to have some advantages over prior art rim fire cartridges. For example, the combination of the adapter and centre fire cartridge can be produced at lower cost, it addresses problems of retention of rim fire cartridges on firing, and gives improved reliability and energy control.

In addition, several different lengths of adapter can be produced so as to restrict the range of ammunition fireable by a specifically adapted weapon. For example the adapter may range from about 4 mm in length to about 30 mm in length, preferably from about 5 mm in length to about 20 mm in length, more preferably from about 6 mm in length to about 10 mm in length. The adapter may be produced with a range of different diameters for use with a range of different cartridges. The diameter of the adapter should conform to the internal diameter of a bore in the cartridge, to enable a snug fit of the adapter in the cartridge, without being immovable. Typical diameters of the adapter may be in the range of from about 3 mm to about 15 mm. By way of example, the adapter may have a diameter of from about 7.0 mm to about 7.1 mm to enable use with 0.22 rimfire firing pin offsets in the adapted weapons.

BRIEF DESCRIPTION OF DRAWINGS

An embodiment of the invention will now be described by way of an example, with reference to the following figures in which:

FIG. 1 shows in cross section a non-lethal, centre fire cartridge fitted with an adapter of the invention.

FIG. 2 shows front and rear views of the adapter shown in FIG. 1.

DETAILED DESCRIPTION OF DRAWINGS

FIG. 1 shows a telescopically expandable cartridge (as is known from the prior art) comprising an anterior portion 1 and posterior portion 2, the posterior portion 2 carries a first primer 3 which when initiated releases gases which propel a ball 4 along a channel 5 to impact upon a second primer 6 in the anterior portion 1.

First primer 3 is configured for centre firing. The cartridge is located in the barrel of a weapon (not shown) which has an off set firing pin 7.

The adapter of the invention 8 is received in a recess in the posterior portion 2 to the rear of the first primer 3 and directly in front of the firing pin 7. As can be seen, the adapter 8 comprises a cylindrical body having an annular recess 9 provided around its outer circumference. An O-ring 10 is received in the annular recess 9. On an anterior surface of the adapter 8 proximal to the first primer 3 is provided a pointed protrusion 11 positioned centrally of the anterior surface.

FIG. 2 a) shows the adapter of FIG. 1 as viewed from the anterior surface. FIG. 2 b) shows the rear surface of the adapter 8. As can be seen, the adapter comprises a solid cylindrical body 8. On the anterior surface, at the centre, a conical protrusion 11 is provided. An O-ring seal 10 extends slightly beyond the outer circumference of the body 8. The rear of the adapter comprises a flat circular surface. 

1. An adapter for translating an impact in an off centre location of the adapter to an impact in a centre location to facilitate the firing of a centre fire primer cartridge by a weapon with an offset firing pin.
 2. An adapter a claimed in claim 1, wherein the adapter comprises a rigid cylinder having a closed end on which is provided a centrally positioned protruding point.
 3. An adapter as claimed in claim 2, wherein the cylinder is solid.
 4. An adapter as claimed in claim 2, wherein the cylinder has an open end and a hollow portion.
 5. An adapter as claimed in claim 2, wherein the adapter comprises a cylindrical body provided with an annular recess into which is received a rubber O-ring.
 6. An adapter as claimed in claim 1, further comprising a seal integrally formed therewith.
 7. An adapter as claimed in claim 1, further comprising a unitary body.
 8. An adapter as claimed in claim 1, further comprising multiple components suitably assembled.
 9. An adapter as claimed in claim 1, wherein the adapter is comprised substantially of metal.
 10. An adapter as claimed in claim 1, wherein the adapter is comprised substantially of a rigid plastic.
 11. A combination of a non-lethal centre fire cartridge including a recess adjacent a centre fire primer and an adapter received in the recess, the adapter having the form as set forth in claim
 1. 12. A combination of a gun with an offset firing pin and an adapter as claimed in claim
 1. 13. A combination is claimed in claim 12, further including a non-lethal centre fire cartridge having a recess adjacent a centre fire primer into which the adapter is received. 